Step 01 – First, install zRootless from the below button for your iOS 12 running iPhone / iPad.
Step 02 – Then Install rootless Jailbreak from zRootless.
Step 03 – Go to Settings, General, Profile and device management to trust the app.
Step 04 – Launch Rootless JB app and tap Jailbreak button to jailbreak your iOS 12 device.
Step 05 – Now install Rootless deb installer using zRootless.
Step 06 – Go back to zRootless and Tap Deb files to install iOS 12 Jailbreak app / tweaks / theme. Copy url and install them using Rootless installer.